Slack-adjuster.



o. P. WILHELM'.

ASL/ICK ADJUSTER.

APPLICATION FILED SEPT. 24, 1914.

1,204,526. I Patented Nov. 14, 1916.

2 SHEETS-SHEET I.

*I f i 0. P. WILHELM..

SLACK ADJUSTER.

APPLICATION FILED SEPT. 24. 1914.

Patented Nov. '14, 1916.

2 SHEETS-SHEET 2.

maman sTaTns PATENT ern/ron.;

OLIVER I. WILHELM, OF MICHIGAN CITY, INDIANA, ASSIGNOR OF TWENTY-FIVEONE- I-IUNDREDTHS TO SANTFORD S. WILHELM AND SEVENTEEN AND ONE-HALF ONE-HUN'DREDTHS T0 LANE WILHELM, BOTH OF MICHIGAN CITY, INDIANA, AND.TWENTY-FIVE ONE-HUNDREDTIIS TO. BEN LOEWENTHAL, OF CHICAGO, ILLINOIS.

SLACK-ADJUSTER.

Lacasse.

Specification of Letters Patent.

Patented Nov.V 14, 1916.

Application filed September 24, 1914. Serial No. 863,287.

new and useful Improvements in Slack- Adjusters; and I do hereby declarethat the following is a full, clear, and exact description of the same,reference being had tothe laccompanying drawings, and to the knumeralsof reference marked thereon, which' form apart of this speciiication.

The wearing down of brake shoes upon a car wheel often causes anineiiicient operation of the brakes, due to the increase in movementrequired ofthe parts of the brake gear. Generally the increase inmovement required effects an improper braking pressure of the shoe uponthe wheel, sometimes with disastrous results.V It is a well known factthat the most efficient braking pressure is that at which only animpending locking of the wheel is occurring, so that the wheel is notpermitted to slide upon the rail.

This invention relates to a mechanism adapted to be connected into thebrake gear to compensate for wear upon the brake shoe, so that the samemovement of the piston in the brake cylinder takes place at all timeswith the result that the brake shoes are applied upon the wheel with apredetermined pressure which is the same throughout thelife of the brakeshoes.

It is an object of this invention toconstruct a take-up or slackadjusting mecha-- nismfor a brake gear which acts to elongateautomatically as necessity requires to obviate excessive movement of theparts in the application o f the brakes.

It is also an important object of this invention to construct a slackadjusting mechanism provided .withj interlocking means for preventingaccidental adjustment thereof due to jarring or other causes other thanthat due to an'increased'. movement resulting from worn b rake shoes.

It is also anobject of this invention to construct a slackadjustingmechanism for connection in a brake gear which acts automatically totake up. .for wear uponthe brake vshoes, Said mehansm Provided' With am?iliary interlocking means to prevent elongation or contraction of" theparts, due to jarring or vibration.

It is also an important object of, this invention to construct a slackadjusting. mechanism for brake gears wherein a plurality 'of slidablemembers are yieldably connected together and inja manner to lock oneanother in various positions of adjustment, whereby the same are held ina fixed position after a change in length of the'mechanism.

It is furthermore an important object of this lnvention to construct acompensating gear adapted to automatically increase lin length to takeup for wear on thevbrake shoes in a brake mechanism, and embodyingadjustably mounted parts yieldably connected one to another. i

. It is nally an object of this invention to construct a simple Y typeof compensating mechanism for brake gears easily assembled and readilyinstalledfor use with standard car equipment, and acting efiiciently toperform the purpose. i

The invention (in .a preferred form) is illustrated in the drawings andhereinafter more fully described. i

In the drawings: Figure lis a conventional diagrammatic view of aportion of a brake gear illustrating a device embodying. the principlesof myinvention connected thereto. Fig. 2 is a fragmentary detail sectiontaken on line 2-2 of Fig. 1. Fig. 3; isa fragmentary top planl view ofthe mechanism shown in Fig. 2. Fig. 4 is a side elevation partly insection showing the relation of the partsin one position of theadjustment, and with the operation illustrated in dotted lines. Fig.y 5is a side elevation of the partsl in'another position of adjustment, andwith the operation illustrated in dotted. lines. Fig. 6 is a detailsection taken on line 6.-6 of Fig. 2. Fig. 7 is a detail section takenon line 7--7 of Fig. 2. Fig. 8 is a detail section taken on line 8-8 ofFig. 2. Fig. 9 is a detail sec tion taken on line 9-9 of Fig. 2.

YAs shown in the drawings: the reference numeral 1, indicates a brakecylinder, and connected to be actuated thereby is a push bar '2'. fAnother push bar 3, is .adjustably connected as hereinafter describedwith the push bar 2, and at its end is linked to a cylinder lever t.Connected on one end of said cylinder lever is a hand brake rod 5, andon the other end thereof is a top rod 6. A floating lever 7, is mountedbeyond the cylinder 1, near the end thereof opposite that near whichsaid cylinder lever 4, is mounted, and connecting said respective levers4 and 7, is a cylinder lever rod 8. One side of said push bar 2, whichis of circular cross section, is provided with a series of ratchet teeth9, and slidably mounted upon said rod is a hollow carriage 10, which iscored out to receive vertically movable therein a toothed ratchet block11, having a coverplate 12, integral therewith for said carriage casing,and provided with a handle or eye on its upper outer surface.

The long push bar 3, is rigidly secured upon said carriage 10, said rodbeing of rectangular cross section, and on its upper surface providedwith a series of ratchet teeth 14, which are directed oppositelyto those9, of the push bar 2. Said ratchet block 11, is provided with a wedgeextension 13, over which the inclined under surface of the end of thepush bar 3, is adapted to engage, thus thrusting said ratchet blockdownwardly into engagement with the teeth of the other push bar 2. Aiixed plate or block 15, through which said push bar 3, slidably eX-tends, is held rigidly secured to another block 16, rigidly connected onthe cylinder, by a plurality of horizontal guide bars or rods 17.Slidably mounted upon said guide bars 17, are blocks or plates 18 and19, respectively, which are also slidable upon said push bar 3, theformer plate provided with a pivoted pawl 20, mounted upon a boss in acutaway portion thereof adapted to engage the teeth 14, of said push bar3, and the latter plate 19, being rigidly connected to said push rod 2.Another series of ratchet teeth 21, is formed on the under side of saidpush bar 3, directed oppositely to the teeth 14C, on the upper sidethereof, and a gravity acting counterweighted pawl 22, is pivoted in acutaway portion of said plate 18, upon aV boss provided for the purpose,and is adapted to engage said ratchet teeth 21. A heavy compressionspring 23,is wound about said push bar 3, between said respective plates18 and 19, and acts to hold the same normally spaced from one another.Accordingly the plate 19, is provided with a small boss 24, around whichone end of said spring 23, engages, and a collar 25, slidable upon thepush'bar 3, restsl against vthe surface of the plate 18 by contactwiththe other end of said compression spring 23. Said spring thrustcollar 25, bears against the tail of the pawl 20, acting to hold thesame normally into position for engagement with the teeth 14, of thepush bar, and also engages the toothed end of the pawl 22, to hold thesame normally engaged with the teeth 21, of said push bar.

Guide bars 18a, -are secured between said plates 18 and 19, to maintainsaid plates properly positioned with respect to one another and to limitthe separation thereof due to the spring 23.

As clearly shown in Figs. 2 and a, the upper portion of the stationaryblock 15, is recessed to permit engagement therein of the toothed end ofthe pawl 20, as the same moves forwardly with the lpush bar, and uponthe under portion of said block 15, is an inclined or taperedeXtension`26, projecting rearwardly from said block which acts when theplate 18, is thrust toward the block, tov engage therethrough, thrustingthe pawl 22, out of engagement with the push bar 3, of course the pawlspringing the lower portion of the collar 25, outwardly when thisoccurs.

The operation is as follows: The device is illustrated in normalposition in Figs 2 and 3. Vhen the mechanism is actuated by the cylinder1, the push rod 2, moves forwardly, thus thrusting the push bar 3,along` by means of the ratchet block 1l, and plate 19, the latter ofwhichA is rigidly connected to the push bar 2, until the plate 18, whichis moved by the plate 19, through the spring 23, contacts the fixedblock or plate 15. It is assumed that when the parts are in properadjustment that the brakes are properly applied at this point in themovement of the gear, but, however, should there be a slack which shouldbe taken up, further movement of the bar 3, by the bar 2, causescompression of the spring 23, and movement of the bar 3, through theblock 18, the pawl 20, tracking over the teeth on said rod 3. However,before such ymovement takes place the pawl 22, is thrown out ofengagement with the teeth 21, on said push bar, due to the projectioninto the' plate 18, of the tapered extension 26, on said plate 15, sothat said pawl 22, which may be termed a safety pawl, is disengagedagainst the compression of the spring 23, springing the collar 25,outwardly at its lower end as said pawl moves into a release position.rlhe movement of the push bar 3, through the plate 18, continues untilthe brakes have been properly applied with the requisite frictionpressure, and then the push bar 2being released by the cylinder 1, movesrearwardly under the compression of the spring 23, in this instancetheratchet block tracking over the teeth 9, until said spring 23, hasexpanded its full amount, permitted by the tie bolts 18L between saidplates 18 and 19, and then both said push bar 3, and said push bar 2,move rearwardly as a unit to retract the brake shoes from the carwheels. It is evident that the moment the plate 18, moves rearwardlyfrom the fixed block 15, that the paw122, is released, and swingsupwardly into engagement with the push rod 3. So long as the mechanismis in proper adjustment, and no slack is evident in the gear, the pushbars 2 and 3, move forwardly as a unit, but in the event of slackoccurring, dueto wear upon the shoes, the spring 23, is compressed, anda relative movement takes place between the respective push bars and therespective ratchet mechanism. to lock the bars in another 'position ofadjustment, 'adding an increment to the length thereof sufficient tocompensate for the difference in movement required. Said pawl 22,engaging the teeth on the under side ofthe push bar 3, prevents the samefrom sliding forwardly independently of the push bar 2, due to jarringor the vibrations of the train.

Figs. 4 and 5 show clearly the position of the parts during an adjustingmovement thereof, the plate ,18, having been moved against the fixedblock 15, and the spring 23, compressed, the slidable block 19 andcarriage 10, then assuming the position shown in dotted lines in Fig.1l. Upon release of the air in the brake cylinders, the parts areextended, due to the spring 23, and the lower push bar 2, is thrustthrough the carriage 10, until the new position of the carriage 10, asshown in full lines in Fig. 5, occurs, the parts then being in properadjustment to insure no slack or excess travel in the brake gear.

I am aware that various details of construction may be varied through awide range without departing from the principles of this invention, andI therefore do not purpose limiting the patent granted otherwise thanvnecessitated by the,prior art.

I claim as my invention:

1. In a device of the class described a plurality of push bars, ratchetteeth formed thereon,` yieldable connections between said push bars,ratchet mechanism for locking said push bars in various extendedpositions to automatically take up slack in a brake gear, and a safetypawl engaging one of said push bars to prevent accidentalmovement-thereof due to jarring or vibration.

2. In a device of the class described slidably connected parallel pushbars, a plate secured on one of said push bars and slidable on the otherthereof, another plate slidable on said latter push bar, a pawl mountedin said latter plate adapted to engage in recesses in said latter pushbar to lock said block and bar together, another pawl mounted in saidplate engaging other recesses in said latter push bar to preventaeeidental movement thereof, a compression spring mounted between saidrespective plates, and mechanism connected to the ]atter of said pushbars and engaging the other'thereofadapted to lock said' push b-arsonefto another.

3. In a device of the class described a pair of push bars, ratchetmechanism mounted on one thereof to lock the same to the other push bar,other ratchet mechanisms slidably mounted on said first mentioned pushbar and yieldably connected to said latter push bar also acting tov locksaid push bars one to another, and a pawl connected to 'one of said pushbarsl and engaging the other push bar to prevent accidental relativemovement between said push bars.

Ll. In a device of the class` described a plurality of push bars, aseries of ratchet teeth oneach thereof, said series directed in oppositedirections, a plurality of ratchet mechanisms adapted to lock said pushbars one to another to automatically take up slack in a brake gear, andmechanism connected to one of said pushr bars adapted to engage theother to prevent accidental relative movement between said push bars. h5. In a device of the class described a plurality of push bars adaptedto be eX- tended relative one another, ratchet teeth in each thereof, aplurality of ratchet mechanisms acting to lock said push bars one toanother in various adjustments after the same have been extended to takeup slack in a brake gear, other ratchet mechanisms preventing accidentalrelative movement between said push bars, and means throwing said latterratchet mechanism out of operation when relative movement between saidpush bars in taking up slack is begun.

6. In a device of the class described automatic slack adjustingmechanism embracing parallel adjustably mounted push bars, -pivotedmeans normally locking the same one to another to prevent accidentalrelative movement therebetween, and spring controlled mechanism actingautomatically to throw said means out of locking position to permitrelative movement between said push bars during an extending operationthereof.

7. In a device of the class described adjustably connected push bars,interlocking means for each thereof, said means acting successively tolock said 'respective push bars in various extended positions, a pivotedelement adapted to maintain said pushv bars locked to one another whennormally out of use to prevent accidental relative movementtherebetween, and means acting to throw said mechanism out of operationduring a take-up movement of said push bars.

8. In a device of the class described adjustably connected push bars,ratchet mechanism secured on one acting to lock the other push bar frommovement in one direction, and ratchet mechanism connected rso on saidlatter bar and acting' to engage said first mentioned bar to lock thesame from movement in the other direction, and safety mechanism toprevent accidental relative movement between said push bars when thesame are normally at rest.

9. In an automatic slack adjusting mechanism slidably connected members,ratchet teeth thereon directed oppositely on said respective members,spring` actuated means connecting one of said members to the other,latching means thereon, yieldably mounted mechanism connecting saidlatter member to said iirst mentioned member through said latchingmeans, and other latching mechanisms normally engaging said members oneto another to prevent accidental relative movement therebetween when thesame are at rest, and automatically thrown out of operation when a slackadjusting' movement is about to take place therebetween.

In witness whereof I have hereunto subscribed my name in the presence oftwo subscribing witnesses.

OLIVER P. WILHELM.

Witnesses CHARLES W. HILLS, Jr., FRANK K. HUDSON.

Copies of this patent may be obtained foi' ve cents each, by addressingthe Commissioner of Patents,

Washington, D. C.

